Couples are left baffled and frustrated when they can't get pregnant, and there's no real explanation.
Around 15% of couples that struggle with infertility have what's called 'unexplained infertility.' Many times, lifestyle changes, medication, or both are effective fertility treatments.
Quick FAQs
Letrozole blocks aromatase, which helps to lower estrogen in the body, resulting in increased ovulation-inducing hormones that increase fertility.
On average, letrozole induces ovulation and increases fertility after 90 days, which is three cycles.
Some of the possible side effects of letrozole include high cholesterol, hot flashes, and fatigue.
Letrozole (Femara) is a common and safe fertility medication that treats ovulation issues in women and unexplained infertility.
Let's look at how Letrozole works for fertility and all of the possible side effects.
While Letrozole is a common breast cancer treatment, the nonsteroidal aromatase inhibitor induces and enhances ovulation and increases pregnancy chances in ovulating women.
By blocking aromatase, Letrozole helps to lower estrogen in the body. As estrogen decreases, you secrete ovulation-inducing hormones that increase fertility. In women with ovulation issues, the increase in follicle-stimulating hormone (FSH) helps develop mature follicles in the ovaries and the ovulation of an egg.
Women that ovulate on their own take letrozole to enhance the release of follicles and eggs. The release of multiple eggs increases the odds of getting pregnant as opposed to just releasing a single egg during your menstrual cycle.
How and when to take Letrozole
Femara and the generic Letrozole come in 2.5 mg dosages. When treating infertility, the dosage will likely be higher.
A doctor will prescribe a patient 2.5mg, 5, or 7.5mg daily for five days. The course of Letrozole will typically fall between the second and sixth day of your menstrual cycle. Your physician will probably recommend intercourse during the five-day regimen.
How many cycles of Letrozole to get pregnant
The response time to fertility drugs varies from woman to woman and is dependent on many factors.
On average, Letrozole induces ovulation and increases fertility after 90 days, which is three cycles.
After one five-day letrozole cycle, ovulation happens in approximately 60% of women, resulting in 24% to 30% of live births.
Side effects of taking Letrozole for fertility
Before prescribing Letrozole or any other fertility treatment, a doctor will explain to you any concerns and side effects of the medication.
The side effects of Letrozole include:
High cholesterol: It happens in about 30% of women taking Letrozole and is manageable for most with a healthy diet and exercise.
Hot flashes and night sweats: Low estrogen causes hot flashes in nearly 20% of those taking letrozole. Eating more fruit and veggies and exercising may ease this side effect.
Fatigue: About 22% of those taking letrozole report feeling tired. Doctors recommend taking the dosage at night and avoid operating heavy machinery.
Nausea: 10% of women report experiencing an upset stomach with letrozole. It's recommended to stay hydrated and eat smaller meals.
Weight change: Some women may experience or weight gain while taking letrozole.
Bone loss: Low levels of estrogen can lead to bone loss, which can put women at risk for fractures. Your healthcare provider will do a scan to check bone loss risk before starting letrozole.
Some women find that the side effects of Letrozole are too severe. Over-the-counter (OTC) supplements and vitamins, such as Fertility Support for Her, may be a more tolerable option.
Don't start a supplement or fertility vitamin unless you discuss it with a medical professional.
Risks and precautions
Research shows that Letrozole is safe to take and doesn't seem to lead to birth defects. But, if you're currently pregnant, stop taking Letrozole, as it can do harm to the fetus.
Letrozole can interact with certain medications, including OTC medications. Advise your doctor about the medicine you're taking to discuss possible adverse reactions - especially any prescription, vitamin, or supplement affecting estrogen levels.
Foods to avoid while taking Letrozole
Most people can eat and drink what they want while taking letrozole. Some patients may experience a loss of appetite.
If this occurs, try eating frequent small meals. In other cases, some women get hungrier when taking Letrozole for infertility, which may require a change in diet.
Discuss with your doctor if you're concerned about a decrease or increase in appetite. Your physician may refer you to a dietitian.
Can you drink alcohol while taking Letrozole?
Some women sometimes experience intense hot flashes, night sweats, and headaches when taking Letrozole.
Medical professionals advise that women should avoid caffeine, smoking, and consuming alcohol when taking fertility drugs to prevent worsening symptoms.
Letrozole For IUI
The purpose of Intrauterine Insemination (IUI) is to increase the number of sperm that reach the uterus and the chances of successful fertilization.
Doctors often prescribe Letrozole in tandem with IUI to stimulate egg growth and induce ovulation.
The success rate after three cycles of IUI with Letrozole is around 15 to 25%.
Letrozole For IVF
A fertility specialist may prescribe Letrozole during IVF to stimulate and regulate your menstrual cycle and increase the odds of getting pregnant.
Researchers have found that taking Letrozole during IVF improves implantation and the rate of successful pregnancies.
Letrozole and Clomid (Clomiphene Citrate) are fertility medications that lower estrogen in the body. Both fertility pills increase fertility by increasing the number of high-quality eggs and inducing ovulation.
While both letrozole and clomid work towards the same goals, the mechanisms of achieving them are different.
Clomid acts as a selective estrogen receptor modulator that blocks estrogen-specific receptors in the brain. In contrast, Letrozole blocks estrogen as a nonsteroidal aromatase inhibitor.
Women experience side effects with Clomid, including:
And while Clomid has been used longer for infertility, research shows that Letrozole is more effective for inducing ovulation and producing more life births.
In one study, 374 women were prescribed Letrozole, while 376 women received Clomid. The treatment lasted for five cycles.
Women that took Letrozole ovulated at a rate of 61.7%, and those that took Clomid ovulated less than 50%.
Letrozole has a higher success rate than Clomid. Women that use Letrozole to induce ovulation have a 15% monthly chance of getting pregnant as long as certain conditions are met.
No other fertility issues.
The female partner is younger than 35.
Ovulation is achieved with Letrozole for women that aren't ovulating.
Takeaways
Multiple studies show that Letrozole is at least as effective as Clomid. In some cases, Letrozole induces ovulation better, leading to more live births.
The effects of Letrozole do differ from woman to woman and are dependent on certain factors.
Fertility specialists often prescribe Letrozole with IUI and IVF to achieve more positive results.
Research continues to answer the question of what letrozole does for fertility. And so far, results of studies have shown Letrozole is safe and effective when trying to induce ovulation for those affected by unexplained infertility.
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Sources:
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